WASHINGTON, DC (WUSA9) -- A couple of appeals court judges had tough questions for a DC lawyer trying to justify the city's regulation of tour guides.

The District requires guides to pass a test and pay $200 in fees before leading visitors around the city's sites.

Two long time guides say the regulation violates their First Amendment free speech rights.

Guiding paid tours without a license in DC can subject you to a $300 fine and three months in jail. "If you are restricted on what you can say on a public street in this country, than there is something wrong with this country," says Tonia Edwards, one of the plaintiffs. She and her husband, Bill Main, have been running their 'Segs In The City' tours for a decade. And they are refusing to take the test or pay the fee.

DC says it has a right to regulate tour guides just as it regulates barbers and plumbers and accountants, to try and insure their customers don't get taken for a ride.

DC won at a trial court but the judges at the Court of Appeals seemed far more skeptical.

Judge Robert Wilkins left a lawyer for the city was flummoxed when he asked her to answer yes or no to this question: Would the guides be breaking the law if led tours but didn't say anything?

"In this country we rely on people to decide on who they want to listen to. We don't rely on the government to decide who is going to get to speak," says Robert McNamara, who argued the case for Edwards and Main, and the non-profit Institute for Justice.

But DC says once people pass the test, they can say whatever they want. The law does not regulate the content of your speech.

The owners of 'Segs in the City' say that is not good enough. "Do you have to go through a hurdle to speak here?" says Edwards. "You get to speak on the street." "It's a principle," says Bill Main. "Freedom of speech."

The two guides and the Institute of Justice say they will keep fighting even if the battle takes them on a tour of the Supreme Court.

It could take a couple of months before we get a decision from the appeals court.